Moog System 55

In 1964, Robert Moog created one of the first modular voltage-controlled music synthesizers, and demonstrated the Moog 55 at the AES convention the same year. The Moog System 55 featured a piano-style keyboard interface and has a logarithmic one volt-per-octave pitch control and a separate pulse triggering signal. The Moog modular synthesizer is considered by enthusiasts to be the original and definitive synthesizer.